It is often desirable to mount an item of plumbing or electrical equipment to a surface. Most commonly, particularly in domestic settings, it is desirable to mount plumbing or electrical equipment to fixed surface such as a wall, or in some cases to a floor or ceiling. In most instances, the installation procedure will involve forming holes in a surface for receiving fixing means such as screws, offering up the item to be mounted, or mounting plates for the item to be mounted, and inserting fixing means through holes in the item or mounting plate, into the fixing holes, to retain the item to the wall or ceiling. There are instances where an item needs to be replaced with a newer item and in these instances, it can be desirable to re-use fixing holes which have already been formed for the item which is being replaced. Further, one of the most time-consuming aspects of an installation process can be accurately measuring up locations for fixing holes to be formed and ensuring that the holes are appropriately formed at the desired locations, as defined by a set of fixed mounting points on the equipment to be mounted. Even when care is taken, the hole-forming equipment, such as a hand held drill, can often ‘wander’ and so the hole may ultimately not be precisely in the initially planned location. Further, it can often be desirable to form the fixing hole or holes at a particular point, for example at a junction between bricks or tiles of a wall or at a particular location relative to pipework or joists in a wall or ceiling. It is not therefore always possible to form a hole where it would most ideally be formed for a particular mounting plate or fixed-location fixing point of an item.